US20080284364A1 - Electronically commutated asynchronous motor - Google Patents
Electronically commutated asynchronous motor Download PDFInfo
- Publication number
- US20080284364A1 US20080284364A1 US12/112,130 US11213008A US2008284364A1 US 20080284364 A1 US20080284364 A1 US 20080284364A1 US 11213008 A US11213008 A US 11213008A US 2008284364 A1 US2008284364 A1 US 2008284364A1
- Authority
- US
- United States
- Prior art keywords
- sensor
- temperature
- motor
- motor according
- rotor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
- G01K7/36—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using magnetic elements, e.g. magnets, coils
Definitions
- the invention relates to an electronically commutated asynchronous motor (ASM) having a stator, a short-circuit rotor, and a controller for field-oriented regulation (FOR) of said motor.
- ASM electronically commutated asynchronous motor
- FOR field-oriented regulation
- Sensing of the electrical parameters of asynchronous motors is important for field-oriented regulation of the motors that are produced.
- FOR field-oriented regulation
- FOR field-oriented regulation
- the instantaneous position and instantaneous absolute value of the rotor-flux space-vector are usually determined with the aid of an analog or digital software model of the motor. All the rotor-flux estimating methods which are based upon a model have the disadvantage, however, that the parallel model can correctly reproduce the motor state only when the parameter values used in the software model agree with the instantaneous parameter values in the particular motor being operated.
- stator resistance and rotor resistance can change by up to 50% as a function of temperature. Changes in main inductance must be compensated for when the ASM is also operated in the field-weakening region.
- this object is achieved by building the motor with a short-circuit rotor which is in thermally conductive relation to a sensor magnet, arranging a rotor position sensor at a predetermined distance from the sensor magnet to produce an output signal dependent upon the spatial orientation of the sensor magnet, evaluating the output signal to ascertain a motor temperature, and using the ascertained motor temperature and the rotor position output signal in a controller for field-oriented regulation (FOR) of the motor.
- FOR field-oriented regulation
- a preferred refinement is to employ a galvanomagnetic sensor as the rotor position sensor.
- a galvanomagnetic rotor position sensor enables a measurement of the temperature of the sensor magnet, and thus allows inferences as to the motor's temperature.
- a further preferred refinement is to employ a magnetoresistive sensor as the rotor position sensor.
- a magnetoresistive sensor enables, for example, a simultaneous measurement of temperature and of rotational angle or position of the rotor, and thus reduces cost.
- a further manner of achieving the object is to place the sensor magnet in thermally conductive relation with the short-circuit rotor, so that the magnetic flux density generated by the sensor magnet in the galvanomagnetic rotor position sensor varies with sensor magnet temperature, and the rotor position output signal amplitude thus becomes a function of temperature.
- This measurement is based on arranging the sensor magnet in thermally conductive connection with the short-circuit rotor, so that the magnetic flux density generated by said sensor magnet is a direct function of rotor temperature.
- motor-specific data are stored in a permanent memory, and this measurement and storage occur at a standardized motor temperature, usually at 20° C. with the aid of these stored data, the temperature that is sensed at the galvanomagnetic sensor can then reliably be calculated, and a motor model is obtained that enables accurate field-oriented regulation.
- FIG. 1 shows a geared motor 200 that operates with field-oriented regulation (FOR);
- FIG. 2 schematically depicts a FOR system
- FIG. 3 is a schematic depiction to explain the invention
- FIG. 4 schematically depicts measurement of a motor temperature by means of a galvanomagnetic sensor
- FIG. 5 shows an output voltage/magnetic flux density characteristic curve of a galvanomagnetic sensor
- FIG. 6 shows an output voltage/temperature characteristic curve of the galvanomagnetic sensor of FIG. 5 ;
- FIG. 7 schematically depicts the measurement of motor temperature by means of an MR (Magneto-Resistive) sensor 18 ′;
- FIG. 8 schematically depicts an evaluation apparatus for processing the temperature-dependent signal from a sensor.
- FIG. 1 shows the basic design of a geared motor 200 that contains a three-phase ASM 12 .
- Said motor has a motor housing 123 , a stator 202 having a three-phase winding, a rotor 204 that is implemented as a so-called short-circuit rotor, and a sensor arrangement 14 A, 18 that preferably sits on a circuit board and is surrounded on the outer side by a sensor housing 124 .
- Rotor 204 has a short-circuit ring 206 at the left end, and a short-circuit ring 208 at the right end.
- Rings 206 , 208 are connected in the usual way by short-circuit bars 210 to form a cage in which a rotor current i R flows during operation, the magnitude of said current being dependent on the temperature of rotor 204 because the resistance of bars 210 increases with increasing temperature. For this reason, the level of the current must be adapted as a function of the rotor temperature and, for this reason, a temperature sensor (the position of which is indicated with the reference character 214 ) has hitherto been integrated into the stator winding, said sensor indirectly sensing the temperature of rotor 204 . The signal from this sensor 214 is delivered to a controller 20 , depicted in FIG. 2 , for the field-oriented regulation (FOR) system.
- FOR field-oriented regulation
- FIG. 2 shows a control arrangement 10 for ASM 12 .
- the latter has a sensor arrangement 14 for generating a rotation speed signal n, as well as a sensor arrangement 14 A ( FIG. 1 ) for generating a Hall signal HALL and a signal MR of a magnetoresistive resistor 18 ( FIG. 2 ).
- a sensor magnet 274 ( FIG. 3 ) is part of sensor arrangement 14 .
- the various signals n, HALL, MR are delivered to an associated multi-pin input 17 ( FIG. 2 ) of a field-oriented regulator (FOR) 20 of known design.
- the latter contains a specific ASIC (Application-Specific Integrated Circuit) 22 that processes the MR signal in order to calculate therefrom the instantaneous rotational position of motor 12 .
- the ASIC furthermore processes the HALL signal in order to calculate therefrom the instantaneous temperature of rotor 204 .
- the HALL signal could also be sent directly outward to an ECU (Electronic Control Unit) 33 ( FIG. 4 ), where temperature calculation would then occur.
- ECU Electronic Control Unit
- the HALL signal is delivered to a measurement arrangement 270 .
- the latter generates therefrom a signal uStand, which is delivered to two inputs SCL and SDA of ASIC 22 as a motor data value, and stored there in an EEPROM (Electrically Erasable Programmable Read-Only Memory) 25 or another, preferably nonvolatile, memory.
- This signal is dependent on the distance d ( FIG. 3 ) between Hall sensor 14 A and sensor magnet 274 that is arranged on an end face of rotor 204 or is thermally conductively connected thereto, and is consequently at the temperature of the rotor.
- the value uStand therefore indicates the standardized value of the Hall signal HALL for the sensor magnet 274 that is being used, at a temperature of 20° C. and at distance d (which is always subject to small manufacturing variations among a series of motors). These variations are largely compensated by the calibration operation.
- motor data the term “motor system data” could also be used, in order to clarify that these are data relevant to the particular motor and the sensor as manufactured.
- Sensor magnet 274 also controls magneto-resistor 18 , which serves for exact sensing of the rotor position.
- the rotor position can, however, also be calculated directly from the Hall signal HALL.
- a value n* for the desired rotation speed of motor 10 is also delivered at an input 50 to FOR 20 . Also delivered thereto are, at inputs 52 , 54 , values i 1 , i 2 , i 3 for the phase currents, and at inputs 56 , 58 , values u 1 , u 2 , u 3 for the phase voltages of the respective phases of motor 12 .
- Currents i 1 etc. are measured, for example, by means of current transformers or measuring resistors 24 of known design, only one of which is depicted since FIG. 1 is a usual symbolic depiction of such a motor.
- motor 12 is supplied with electrical energy via a rectifier 26 from a three-phase network U, V, W.
- Rectifier 26 feeds into a DC link circuit lead 28 (negative) and lead 30 (positive), to which a capacitor 32 is connected as a reactive current source.
- DC link circuit 28 , 30 could of course be connected in the same fashion directly to a battery, e.g. to the battery of a vehicle, as is well known to the skilled artisan.
- DC link circuit 28 , 30 Connected to DC link circuit 28 , 30 is a three-phase inverter 34 , only one of whose three branches is depicted.
- the latter contains power MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) 36 , 38 , which are controlled via associated outputs 40 , 42 of FOR 20 by means of PWM (Pulse Width Modulation) pulses that are indicated symbolically in FIG. 2 .
- MOSFETs Metal Oxide Semiconductor Field Effect Transistors
- ASIC 22 of Hall sensor 14 A receives the HALL signal that is dependent on temperature, and because a baseline value corresponding to a temperature of 20° C. is stored in EEPROM 25 , ASIC 22 can continuously recalculate the instantaneous temperature and, proceeding therefrom, control the currents in motor 12 so as to yield the desired torque or desired rotation speed.
- magneto-resistor 18 is also controlled by the same sensor magnet 274 , so that in this manner both the instantaneous rotation angle position of rotor 204 and the instantaneous rotor temperature can be calculated using only one sensor magnet 274 , resulting in a very compact design.
- FIG. 4 schematically depicts stator 202 ; rotor 204 , having short-circuit bars 210 and sensor magnet 274 ; galvanomagnetic sensor 14 A; MR sensor 18 for sensing the rotor position angle phi; and ECU (Electronic Control Unit) 33 , which has a FOR controller 20 and a temperature evaluation apparatus 44 .
- Stator 202 generates a magnetic flux density B 100 by which a current i R 102 is induced in short-circuit rotor 204 .
- a torque at rotor 204 is also generated thereby, with the result that the rotor rotates and rotor position angle phi changes.
- current i R causes a power dissipation that increases temperature T_M 104 of rotor 204 and of motor 12 in general.
- temperature T_M 104 influences temperature T_SM 106 of sensor magnet 274 , so that
- T_SM T_M (1).
- sensor magnet 274 is nonrotatably secured to rotor 204 , for example by way of a thermally conductive material.
- Sensor magnet 274 rotates along with rotor 204 and generates a magnetic flux density B(phi,T_SM) 108 that is dependent on rotor position angle phi and on temperature T_SM 106 of sensor magnet 274 , the amplitude of magnetic flux density B 108 decreasing with increasing temperature T_SM 106 of sensor magnet 274 .
- Galvanomagnetic sensor 14 A detects magnetic flux density B 108 at the location of sensor 14 A, and generates an output signal HALL 110 whose voltage U 112 takes substantially the form
- Voltage U 112 that is ascertained, is delivered to temperature evaluation apparatus CALC_T 44 .
- temperature evaluation apparatus CALC_T 44 By evaluating the amplitude f(T_SM), it is now possible to determine temperature T_SM 106 of sensor magnet 274 , which temperature corresponds, to a good approximation, to temperature T_M 104 of short-circuit rotor 204 .
- Temperature value T 45 that is ascertained is then delivered to FOR controller 20 , and the latter can perform improved field-oriented regulation with the aid of value T 45 and rotor position angle phi ascertained by MR sensor 18 .
- a measurement of the temperature-dependent magnetic flux density 108 using a galvanomagnetic sensor 14 A reacts more quickly to temperature changes in motor 12 than a measurement of the temperature at the location of sensor 14 A (for example using an “NTC” Negative Temperature Coefficient resistor), since thermal transfer does not occur instantaneously, and a temperature measurement at the location of sensor 14 A is therefore delayed in time with respect to the temperature of the motor.
- NTC Negative Temperature Coefficient resistor
- Predetermined distance d ( FIG. 3 ) between sensor magnet 274 and galvanomagnetic sensor 14 A is preferably selected in such a way that it is approximately two-thirds of radius r_SM 120 of sensor magnet 274 .
- r_SM is approximately 7 mm, and d is thus approximately 5 mm.
- stator-side separating member or partition or cap 122 ( FIG. 1 ) is provided between sensor 14 A and sensor magnet 274 , e.g. in order to protect sensor 14 A from internal motor media such as, for example, oil
- cap 122 is preferably implemented using a poorly thermally conductive material such as, for example, plastic, in order to reduce heating of sensor 14 A.
- sensor 14 A can be thermally connected in highly thermally conductive fashion to sensor housing 124 ( FIG. 1 ), in order to keep the temperature of sensor 14 A approximately at external temperature. In the case of galvanomagnetic sensors 14 A having an output signal 110 that is dependent on the temperature of sensor 14 A, this reduces the influence on output signal 110 due to heating of sensor 14 A, thus simplifying evaluation.
- Galvanomagnetic sensors 14 A with compensation for dependence on the sensor temperature are preferably used. Such compensation is possible, for example, in the silicon of sensor 14 A.
- a suitable galvanomagnetic sensor 14 A is, for example, the HW- 101 A Hall sensor of the Asahi Kasei EMD Corporation (AKE).
- FIG. 5 shows, from the data sheet of the HW- 101 A Hall sensor, a V H -B characteristic curve with output voltage V H and magnetic flux density B; and FIG. 6 shows a V H -T characteristic curve with output voltage V H and temperature T.
- output voltage V H rises linearly with the absolute value of magnetic flux density B, provided the input voltage V C is held constant.
- curve 144 in FIG. 6 the value of output voltage V H remains substantially constant in the operating temperature region from ⁇ 40° C. to +110° C. for a constant input voltage V C .
- Voltage U 112 ( FIG. 4 ) generated by Hall sensor 14 A thus depends substantially on the (directionally independent) magnetic flux density B.
- FIG. 7 schematically depicts a measurement of motor temperature T_M 104 using an MR sensor 18 ′ arranged centrally with respect to rotor axis 150 .
- stator 202 and rotor 204 relevant to the heating of motor 12 correspond to those of FIG. 4 , and will not be described again.
- temperature T_SM of sensor magnet 274 represents a sufficient mapping of temperature T_M 104 of short-circuit rotor 204 .
- MR sensor 18 ′ e.g. an Anisotropic Magneto-Resistive (AMR), a Giant Magneto-Resistive (GMR), or a Colossal Magneto-Resistive (CMR) sensor
- AMR Anisotropic Magneto-Resistive
- GMR Giant Magneto-Resistive
- CMR Colossal Magneto-Resistive
- output voltage U 1 is delivered to temperature evaluation apparatus CALC_T in order to ascertain temperature T
- output voltages U 1 and U 2 are delivered to FOR controller 20 in order to ascertain rotor position angle phi.
- MR sensors 18 ′ whose output signals 130 , 132 depend, in the specified region, very little on the strength of magnetic flux density B 108 , but instead principally on the direction thereof (also called the magnetic field direction), or to use sensors in which the dependence on magnetic flux density B at least is less than the dependence on the temperature of MR sensor 18 ′.
- the output voltage drops by approximately 0.29%/K as temperature T_S rises, and in the working region (usually in the saturation region with respect to magnetic flux density B), said voltage is substantially independent of the magnitude of magnetic flux density B.
- the working region with respect to temperature is ⁇ 40° C. to +125° Celsius.
- temperature (T_S) 140 of sensor 18 ′ can be determined, said temperature corresponding approximately to temperature T_SM 106 of sensor magnet 274 ; this temperature in turn corresponds, to a good approximation, to temperature (T_M) 104 of short-circuit rotor 204 .
- the measurement is not as accurate as, for example, a direct measurement in short-circuit rotor 204 or a measurement using a galvanomagnetic sensor as in FIG. 4 , especially in a context of rapidly changing temperatures, but is still accurate enough for many applications.
- the approach is very favorable because both rotor position angle phi and the approximate temperature (T_M) 104 of short-circuit rotor 204 can be ascertained using MR sensor 140 .
- Predetermined distance d between sensor magnet 274 and MR sensor 18 ′ is preferably selected to be small, e.g. 1 mm to 4 mm, more preferably 1.5 to 3 mm, in order to enable good thermal transfer 134 .
- a stator-side partition or cap 122 ( FIG. 1 ) can be provided between sensor 18 ′ and sensor magnet 274 in order to protect sensor 18 ′.
- partition 122 is fabricated from a highly thermally conductive material such as, for example, a metal, in particular aluminum.
- sensor 18 or 18 ′ can be thermally insulated with respect to the usually highly-thermally-conductive sensor housing 124 ( FIG. 1 ), in order to reduce cooling caused by the latter.
- FIG. 8 shows an exemplifying embodiment of a temperature evaluation apparatus (temperature ascertaining apparatus, temperature sensing apparatus) 44 for evaluating a temperature-dependent sensor signal U 1 from a galvanomagnetic sensor 14 A ( FIG. 4 ) or from an MR sensor 18 ′ ( FIG. 7 ).
- a temperature evaluation apparatus temperature ascertaining apparatus, temperature sensing apparatus 44 for evaluating a temperature-dependent sensor signal U 1 from a galvanomagnetic sensor 14 A ( FIG. 4 ) or from an MR sensor 18 ′ ( FIG. 7 ).
- Apparatus 44 is implemented here as an ASIC, but can also be embodied, for example, in a microprocessor or microcontroller.
- the temperature-dependent signal U 1 is delivered to an A/D (Analog-to-Digital) converter 304 , where it is digitized.
- Output signal U 1 _dig is delivered to a FIND_MAX function 308 and to a FIND_MIN function 310 that ascertain, for example over a predetermined time span, the maximum value MAX_U 1 312 and minimum value MIN_U 1 314 . This is done by, for example, ascertaining the greatest value and smallest value during one period of the sinusoidal signal U 1 .
- Amplitude AMPL is then calculated at 316 by calculating half the difference between maximum value MAX_U 1 and minimum value MIN_U 1 .
- temperature T is then ascertained by means of a function g(AMPL, PAR), from amplitude AMPL and, if applicable, from further parameters PAR that are dependent on the motor or sensor.
- Motor-dependent parameters PAR are stored, for example, in an EEPROM 320 ( FIG. 8 ).
- the temperature determination can be dependent, for example, on the measurement method, sensor type, sensor arrangement, production series variations during sensor manufacture, etc.
- parameters PAR 320 can be predefined for the motor type; for greater accuracy requirements or high tolerances, however, an at least partial stipulation of parameters ascertained for each individual rotor 204 may also be necessary, in which context, for example, measurements are performed at predetermined temperatures.
- the temperature can be ascertained either from only one of the two signals, or from both.
- a sine signal and cosine signal are detected, they can be plotted in known fashion as a circle, and the temperature is determined from the radius of the circle.
- the present method of temperature measurement can also be used with BLDC (Brush-Less Direct Current) motors or electronically commutated DC motors to permit, in such motors, regulation with a more accurate motor model.
- BLDC Battery-Less Direct Current
- electronically commutated DC motors to permit, in such motors, regulation with a more accurate motor model.
- sensors 14 A or 18 , 18 ′ that are dependent, inter alia, both on the absolute value of magnetic flux density B and on temperature T_S of sensor 18 , 18 ′. This may complicate evaluation, however, and the effects can cancel or negatively affect one another.
- the characteristic curve of the ascertained voltage as a function of motor temperature must be measured beforehand, as applicable, in motor 12 .
- both are preferably arranged on the same side of the circuit board; with one galvanomagnetic and one MR sensor, preferably either both sensors are arranged on the same side of the circuit board, or one of the sensors is arranged on the front side of the circuit board and the other on its back side.
- MR sensors are preferably arranged in the region of rotation axis 150 ( FIG. 4 , FIG. 7 ) of the rotor or of sensor magnet 106 , and thus centrally; while galvanomagnetic sensors, especially when used exclusively to ascertain temperature, can be positioned relatively freely provided the magnetic flux density at the selected position is high enough.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Control Of Motors That Do Not Use Commutators (AREA)
- Photoreceptors In Electrophotography (AREA)
- Brushless Motors (AREA)
Abstract
Description
- This application claims priority of German
patent applications DE 10 2007 024 244.3 & 10 2007 039 366.2, filed respectively 14 May 2007 and 15 Aug. 2007, the entire contents of which are hereby incorporated by reference. - The invention relates to an electronically commutated asynchronous motor (ASM) having a stator, a short-circuit rotor, and a controller for field-oriented regulation (FOR) of said motor.
- Sensing of the electrical parameters of asynchronous motors (ASMs) is important for field-oriented regulation of the motors that are produced.
- Although field-oriented regulation (FOR) of asynchronous motors is known, its vulnerability or sensitivity to changes in parameters represents a problem that has not satisfactorily been solved. In FOR, regulation takes place in a coordinate system oriented on the rotor-flux space-vector, so that the flux-forming and torque-forming current components can be influenced separately. The instantaneous position and instantaneous absolute value of the rotor-flux space-vector are usually determined with the aid of an analog or digital software model of the motor. All the rotor-flux estimating methods which are based upon a model have the disadvantage, however, that the parallel model can correctly reproduce the motor state only when the parameter values used in the software model agree with the instantaneous parameter values in the particular motor being operated.
- During operation, the stator resistance and rotor resistance can change by up to 50% as a function of temperature. Changes in main inductance must be compensated for when the ASM is also operated in the field-weakening region.
- It is therefore an object of the invention to provide a novel electronically commutated asynchronous motor that is particularly adapted to operate using field-oriented regulation.
- According to the present invention, this object is achieved by building the motor with a short-circuit rotor which is in thermally conductive relation to a sensor magnet, arranging a rotor position sensor at a predetermined distance from the sensor magnet to produce an output signal dependent upon the spatial orientation of the sensor magnet, evaluating the output signal to ascertain a motor temperature, and using the ascertained motor temperature and the rotor position output signal in a controller for field-oriented regulation (FOR) of the motor. The temperature of the rotor can thereby very easily be measured in a contact-free manner.
- A preferred refinement is to employ a galvanomagnetic sensor as the rotor position sensor. The use of a galvanomagnetic rotor position sensor enables a measurement of the temperature of the sensor magnet, and thus allows inferences as to the motor's temperature.
- A further preferred refinement is to employ a magnetoresistive sensor as the rotor position sensor. The use of a magnetoresistive sensor enables, for example, a simultaneous measurement of temperature and of rotational angle or position of the rotor, and thus reduces cost.
- A further manner of achieving the object is to place the sensor magnet in thermally conductive relation with the short-circuit rotor, so that the magnetic flux density generated by the sensor magnet in the galvanomagnetic rotor position sensor varies with sensor magnet temperature, and the rotor position output signal amplitude thus becomes a function of temperature. This measurement is based on arranging the sensor magnet in thermally conductive connection with the short-circuit rotor, so that the magnetic flux density generated by said sensor magnet is a direct function of rotor temperature.
- Because individual motors differ from one another as produced, it is particularly advantageous to calibrate or compensate at the end of motor fabrication, i.e. during production, motor-specific data are stored in a permanent memory, and this measurement and storage occur at a standardized motor temperature, usually at 20° C. with the aid of these stored data, the temperature that is sensed at the galvanomagnetic sensor can then reliably be calculated, and a motor model is obtained that enables accurate field-oriented regulation.
- Further details and advantageous refinements of the invention are evident from the exemplifying embodiments, in no way to be understood as a limitation of the invention, that are described below and depicted in the drawings:
-
FIG. 1 shows a gearedmotor 200 that operates with field-oriented regulation (FOR); -
FIG. 2 schematically depicts a FOR system; -
FIG. 3 is a schematic depiction to explain the invention; -
FIG. 4 schematically depicts measurement of a motor temperature by means of a galvanomagnetic sensor; -
FIG. 5 shows an output voltage/magnetic flux density characteristic curve of a galvanomagnetic sensor; -
FIG. 6 shows an output voltage/temperature characteristic curve of the galvanomagnetic sensor ofFIG. 5 ; -
FIG. 7 schematically depicts the measurement of motor temperature by means of an MR (Magneto-Resistive)sensor 18′; and -
FIG. 8 schematically depicts an evaluation apparatus for processing the temperature-dependent signal from a sensor. -
FIG. 1 shows the basic design of a gearedmotor 200 that contains a three-phase ASM 12. Said motor has amotor housing 123, astator 202 having a three-phase winding, arotor 204 that is implemented as a so-called short-circuit rotor, and asensor arrangement sensor housing 124.Rotor 204 has a short-circuit ring 206 at the left end, and a short-circuit ring 208 at the right end.Rings circuit bars 210 to form a cage in which a rotor current iR flows during operation, the magnitude of said current being dependent on the temperature ofrotor 204 because the resistance ofbars 210 increases with increasing temperature. For this reason, the level of the current must be adapted as a function of the rotor temperature and, for this reason, a temperature sensor (the position of which is indicated with the reference character 214) has hitherto been integrated into the stator winding, said sensor indirectly sensing the temperature ofrotor 204. The signal from thissensor 214 is delivered to acontroller 20, depicted inFIG. 2 , for the field-oriented regulation (FOR) system. -
FIG. 2 shows acontrol arrangement 10 for ASM 12. The latter has asensor arrangement 14 for generating a rotation speed signal n, as well as asensor arrangement 14A (FIG. 1 ) for generating a Hall signal HALL and a signal MR of a magnetoresistive resistor 18 (FIG. 2 ). A sensor magnet 274 (FIG. 3 ) is part ofsensor arrangement 14. - The various signals n, HALL, MR are delivered to an associated multi-pin input 17 (
FIG. 2 ) of a field-oriented regulator (FOR) 20 of known design. The latter contains a specific ASIC (Application-Specific Integrated Circuit) 22 that processes the MR signal in order to calculate therefrom the instantaneous rotational position ofmotor 12. The ASIC furthermore processes the HALL signal in order to calculate therefrom the instantaneous temperature ofrotor 204. The HALL signal could also be sent directly outward to an ECU (Electronic Control Unit) 33 (FIG. 4 ), where temperature calculation would then occur. - For this, as shown in
FIG. 3 , at a predetermined temperature, e.g. 20° C., the HALL signal is delivered to ameasurement arrangement 270. The latter generates therefrom a signal uStand, which is delivered to two inputs SCL and SDA ofASIC 22 as a motor data value, and stored there in an EEPROM (Electrically Erasable Programmable Read-Only Memory) 25 or another, preferably nonvolatile, memory. This signal is dependent on the distance d (FIG. 3 ) betweenHall sensor 14A andsensor magnet 274 that is arranged on an end face ofrotor 204 or is thermally conductively connected thereto, and is consequently at the temperature of the rotor. The value uStand therefore indicates the standardized value of the Hall signal HALL for thesensor magnet 274 that is being used, at a temperature of 20° C. and at distance d (which is always subject to small manufacturing variations among a series of motors). These variations are largely compensated by the calibration operation. Instead of “motor data,” the term “motor system data” could also be used, in order to clarify that these are data relevant to the particular motor and the sensor as manufactured. -
Sensor magnet 274 also controls magneto-resistor 18, which serves for exact sensing of the rotor position. The rotor position can, however, also be calculated directly from the Hall signal HALL. - A value n* for the desired rotation speed of
motor 10 is also delivered at aninput 50 to FOR 20. Also delivered thereto are, atinputs inputs motor 12. Currents i1 etc. are measured, for example, by means of current transformers or measuringresistors 24 of known design, only one of which is depicted sinceFIG. 1 is a usual symbolic depiction of such a motor. - In this example,
motor 12 is supplied with electrical energy via arectifier 26 from a three-phase network U, V, W. Rectifier 26 feeds into a DC link circuit lead 28 (negative) and lead 30 (positive), to which acapacitor 32 is connected as a reactive current source.DC link circuit - Connected to
DC link circuit outputs 40, 42 of FOR 20 by means of PWM (Pulse Width Modulation) pulses that are indicated symbolically inFIG. 2 . - Because ASIC 22 of
Hall sensor 14A (FIG. 3 ) receives the HALL signal that is dependent on temperature, and because a baseline value corresponding to a temperature of 20° C. is stored in EEPROM 25, ASIC 22 can continuously recalculate the instantaneous temperature and, proceeding therefrom, control the currents inmotor 12 so as to yield the desired torque or desired rotation speed. InFIG. 3 , magneto-resistor 18 is also controlled by thesame sensor magnet 274, so that in this manner both the instantaneous rotation angle position ofrotor 204 and the instantaneous rotor temperature can be calculated using only onesensor magnet 274, resulting in a very compact design. -
FIG. 4 schematically depictsstator 202;rotor 204, having short-circuit bars 210 andsensor magnet 274;galvanomagnetic sensor 14A;MR sensor 18 for sensing the rotor position angle phi; and ECU (Electronic Control Unit) 33, which has aFOR controller 20 and atemperature evaluation apparatus 44. -
Stator 202 generates a magneticflux density B 100 by which acurrent i R 102 is induced in short-circuit rotor 204. A torque atrotor 204 is also generated thereby, with the result that the rotor rotates and rotor position angle phi changes. Especially as a result of the resistance of short-circuit bars 210, current iR causes a power dissipation that increases temperature T_M 104 ofrotor 204 and ofmotor 12 in general. - As a result of
thermal transfer 105, in particular thermal conduction, temperature T_M 104influences temperature T_SM 106 ofsensor magnet 274, so that -
T_SM=T_M (1). - For this purpose,
sensor magnet 274 is nonrotatably secured torotor 204, for example by way of a thermally conductive material. -
Sensor magnet 274 rotates along withrotor 204 and generates a magnetic flux density B(phi,T_SM) 108 that is dependent on rotor position angle phi and ontemperature T_SM 106 ofsensor magnet 274, the amplitude of magneticflux density B 108 decreasing with increasingtemperature T_SM 106 ofsensor magnet 274. -
Galvanomagnetic sensor 14A detects magneticflux density B 108 at the location ofsensor 14A, and generates anoutput signal HALL 110 whosevoltage U 112 takes substantially the form -
U=f(T — SM)*sin(phi) (2). - Voltage U112, that is ascertained, is delivered to temperature
evaluation apparatus CALC_T 44. By evaluating the amplitude f(T_SM), it is now possible to determinetemperature T_SM 106 ofsensor magnet 274, which temperature corresponds, to a good approximation, to temperature T_M 104 of short-circuit rotor 204.Temperature value T 45 that is ascertained is then delivered to FORcontroller 20, and the latter can perform improved field-oriented regulation with the aid ofvalue T 45 and rotor position angle phi ascertained byMR sensor 18. - A measurement of the temperature-dependent
magnetic flux density 108 using agalvanomagnetic sensor 14A reacts more quickly to temperature changes inmotor 12 than a measurement of the temperature at the location ofsensor 14A (for example using an “NTC” Negative Temperature Coefficient resistor), since thermal transfer does not occur instantaneously, and a temperature measurement at the location ofsensor 14A is therefore delayed in time with respect to the temperature of the motor. - Predetermined distance d (
FIG. 3 ) betweensensor magnet 274 andgalvanomagnetic sensor 14A is preferably selected in such a way that it is approximately two-thirds ofradius r_SM 120 ofsensor magnet 274. For apreferred sensor magnet 274, r_SM is approximately 7 mm, and d is thus approximately 5 mm. - If a stator-side separating member or partition or cap 122 (
FIG. 1 ) is provided betweensensor 14A andsensor magnet 274, e.g. in order to protectsensor 14A from internal motor media such as, for example, oil,cap 122 is preferably implemented using a poorly thermally conductive material such as, for example, plastic, in order to reduce heating ofsensor 14A. Additionally or alternatively,sensor 14A can be thermally connected in highly thermally conductive fashion to sensor housing 124 (FIG. 1 ), in order to keep the temperature ofsensor 14A approximately at external temperature. In the case ofgalvanomagnetic sensors 14A having anoutput signal 110 that is dependent on the temperature ofsensor 14A, this reduces the influence onoutput signal 110 due to heating ofsensor 14A, thus simplifying evaluation. -
Galvanomagnetic sensors 14A with compensation for dependence on the sensor temperature are preferably used. Such compensation is possible, for example, in the silicon ofsensor 14A. - A suitable
galvanomagnetic sensor 14A is, for example, the HW-101A Hall sensor of the Asahi Kasei EMD Corporation (AKE). - An approach without an
MR sensor galvanomagnetic sensors 14A operating in an analog manner are used in order to generate two non-identical sine-wave signals, preferably a sine signal and a cosine signal. The temperature can then be ascertained either from one signal or from both signals. -
FIG. 5 shows, from the data sheet of the HW-101A Hall sensor, a VH-B characteristic curve with output voltage VH and magnetic flux density B; andFIG. 6 shows a VH-T characteristic curve with output voltage VH and temperature T. As is evident from curve 142 ofFIG. 5 , output voltage VH rises linearly with the absolute value of magnetic flux density B, provided the input voltage VC is held constant. It is evident fromcurve 144 inFIG. 6 that the value of output voltage VH remains substantially constant in the operating temperature region from −40° C. to +110° C. for a constant input voltage VC. - Voltage U112 (
FIG. 4 ) generated byHall sensor 14A thus depends substantially on the (directionally independent) magnetic flux density B. -
FIG. 7 schematically depicts a measurement of motor temperature T_M 104 using anMR sensor 18′ arranged centrally with respect torotor axis 150. - The mechanisms in
stator 202 androtor 204 relevant to the heating ofmotor 12 correspond to those ofFIG. 4 , and will not be described again. - The starting point is once again the fact that temperature T_SM of
sensor magnet 274 represents a sufficient mapping of temperature T_M 104 of short-circuit rotor 204. - Unlike
FIG. 4 ,MR sensor 18′ (e.g. an Anisotropic Magneto-Resistive (AMR), a Giant Magneto-Resistive (GMR), or a Colossal Magneto-Resistive (CMR) sensor) is positioned relative tosensor magnet 274 in such a way that athermal transfer 134 takes place fromsensor 274 tosensor 18′, in particular by thermal radiation and convection. Model GF705 from Sensitec GmbH of Lahnau, Germany is suitable as a GMR sensor. - When an
MR sensor 18′ havingoutputs -
U1=f(T — S)sin(phi) (3) -
U2=f(T — S)cos(phi) (4) - depend on rotor position angle phi and on
temperature T_S 140 ofsensor 18′, and they are delivered toECU 33, in which, for example, output voltage U1 is delivered to temperature evaluation apparatus CALC_T in order to ascertain temperature T, and output voltages U1 and U2 are delivered to FORcontroller 20 in order to ascertain rotor position angle phi. - It is preferred to use
MR sensors 18′ whose output signals 130, 132 depend, in the specified region, very little on the strength of magneticflux density B 108, but instead principally on the direction thereof (also called the magnetic field direction), or to use sensors in which the dependence on magnetic flux density B at least is less than the dependence on the temperature ofMR sensor 18′. - In the case of the KMZ43T MR sensor of Philips Electronics NV, for example, the output voltage drops by approximately 0.29%/K as temperature T_S rises, and in the working region (usually in the saturation region with respect to magnetic flux density B), said voltage is substantially independent of the magnitude of magnetic flux density B. The working region with respect to temperature is −40° C. to +125° Celsius.
- By evaluating amplitude f(T_S) in
CALC_T 44, temperature (T_S) 140 ofsensor 18′ can be determined, said temperature corresponding approximately totemperature T_SM 106 ofsensor magnet 274; this temperature in turn corresponds, to a good approximation, to temperature (T_M) 104 of short-circuit rotor 204. - Because of the double indirect measurement, the measurement is not as accurate as, for example, a direct measurement in short-
circuit rotor 204 or a measurement using a galvanomagnetic sensor as inFIG. 4 , especially in a context of rapidly changing temperatures, but is still accurate enough for many applications. The approach is very favorable because both rotor position angle phi and the approximate temperature (T_M) 104 of short-circuit rotor 204 can be ascertained usingMR sensor 140. - Predetermined distance d between
sensor magnet 274 andMR sensor 18′ is preferably selected to be small, e.g. 1 mm to 4 mm, more preferably 1.5 to 3 mm, in order to enable goodthermal transfer 134. - As in the case of the variant having
galvanomagnetic sensor 14A, here as well, a stator-side partition or cap 122 (FIG. 1 ) can be provided betweensensor 18′ andsensor magnet 274 in order to protectsensor 18′. - For good
thermal transfer 134,partition 122 is fabricated from a highly thermally conductive material such as, for example, a metal, in particular aluminum. - In addition,
sensor FIG. 1 ), in order to reduce cooling caused by the latter. -
FIG. 8 shows an exemplifying embodiment of a temperature evaluation apparatus (temperature ascertaining apparatus, temperature sensing apparatus) 44 for evaluating a temperature-dependent sensor signal U1 from agalvanomagnetic sensor 14A (FIG. 4 ) or from anMR sensor 18′ (FIG. 7 ). -
Apparatus 44 is implemented here as an ASIC, but can also be embodied, for example, in a microprocessor or microcontroller. - The temperature-dependent signal U1 is delivered to an A/D (Analog-to-Digital)
converter 304, where it is digitized. Output signal U1_dig is delivered to aFIND_MAX function 308 and to aFIND_MIN function 310 that ascertain, for example over a predetermined time span, themaximum value MAX_U1 312 andminimum value MIN_U1 314. This is done by, for example, ascertaining the greatest value and smallest value during one period of the sinusoidal signal U1. Amplitude AMPL is then calculated at 316 by calculating half the difference between maximum value MAX_U1 and minimum value MIN_U1. - At 318 temperature T is then ascertained by means of a function g(AMPL, PAR), from amplitude AMPL and, if applicable, from further parameters PAR that are dependent on the motor or sensor. Motor-dependent parameters PAR are stored, for example, in an EEPROM 320 (
FIG. 8 ). The temperature determination can be dependent, for example, on the measurement method, sensor type, sensor arrangement, production series variations during sensor manufacture, etc. For applications with lesser accuracy requirements or low tolerances,parameters PAR 320 can be predefined for the motor type; for greater accuracy requirements or high tolerances, however, an at least partial stipulation of parameters ascertained for eachindividual rotor 204 may also be necessary, in which context, for example, measurements are performed at predetermined temperatures. - If two rotor position signals are present, as is the case for example when an MR sensor or two galvanomagnetic sensors are used, the temperature can be ascertained either from only one of the two signals, or from both. When a sine signal and cosine signal are detected, they can be plotted in known fashion as a circle, and the temperature is determined from the radius of the circle.
- The present method of temperature measurement can also be used with BLDC (Brush-Less Direct Current) motors or electronically commutated DC motors to permit, in such motors, regulation with a more accurate motor model.
- It is also possible to use
sensors sensor motor 12. - When at least two sensors are used, it is advantageous to arrange both on a common circuit board. With two galvanomagnetic sensors, both are preferably arranged on the same side of the circuit board; with one galvanomagnetic and one MR sensor, preferably either both sensors are arranged on the same side of the circuit board, or one of the sensors is arranged on the front side of the circuit board and the other on its back side. MR sensors are preferably arranged in the region of rotation axis 150 (
FIG. 4 ,FIG. 7 ) of the rotor or ofsensor magnet 106, and thus centrally; while galvanomagnetic sensors, especially when used exclusively to ascertain temperature, can be positioned relatively freely provided the magnetic flux density at the selected position is high enough. - Many variants and modifications are of course possible within the scope of the invention.
Claims (26)
Applications Claiming Priority (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102007024244 | 2007-05-14 | ||
DE102007024244 | 2007-05-14 | ||
DE102007024244.3 | 2007-05-14 | ||
DE102007039366 | 2007-08-15 | ||
DE102007039366.2 | 2007-08-15 | ||
DE102007039366 | 2007-08-15 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20080284364A1 true US20080284364A1 (en) | 2008-11-20 |
US7936145B2 US7936145B2 (en) | 2011-05-03 |
Family
ID=39689169
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/112,130 Expired - Fee Related US7936145B2 (en) | 2007-05-14 | 2008-04-30 | Electronically commutated asynchronous motor |
Country Status (4)
Country | Link |
---|---|
US (1) | US7936145B2 (en) |
EP (1) | EP1992927B1 (en) |
AT (1) | ATE507465T1 (en) |
DE (2) | DE502008003332D1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102594032A (en) * | 2011-01-14 | 2012-07-18 | 瑞美技术有限责任公司 | Electric machine having an integrated rotor temperature sensor |
US20120187888A1 (en) * | 2011-01-25 | 2012-07-26 | Marco Bussa | Voltage regulating device |
US20140355644A1 (en) * | 2013-05-31 | 2014-12-04 | Purdue Research Foundation | Wireless Sensor for Rotating Elements |
CN107192972A (en) * | 2017-05-17 | 2017-09-22 | 常楚笛 | A kind of MRI system and its imaging method |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102009001955A1 (en) * | 2009-03-27 | 2010-10-07 | Beckhoff Automation Gmbh | Method and amplifier for operating a synchronous motor |
DE102009028749A1 (en) * | 2009-08-20 | 2011-02-24 | Robert Bosch Gmbh | Temperature detection by magnetic field changes |
JP5895774B2 (en) * | 2012-09-04 | 2016-03-30 | 株式会社安川電機 | motor |
DE102015012902A1 (en) | 2015-10-06 | 2017-04-06 | Audi Ag | Method for determining a temperature of a rotor |
DE102016214497A1 (en) * | 2016-08-05 | 2018-02-08 | Schaeffler Technologies AG & Co. KG | Control unit and method for controlling an electric machine |
WO2019124985A1 (en) * | 2017-12-20 | 2019-06-27 | Samsung Electronics Co., Ltd. | Motor and washing machine having the same |
DE102022213833A1 (en) | 2022-12-19 | 2023-12-14 | Vitesco Technologies GmbH | Electric machine, sensor device, evaluation unit and method for detecting a temperature of a rotor |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3848466A (en) * | 1974-01-30 | 1974-11-19 | Atomic Energy Commission | Magnetic temperature sensor |
US4567419A (en) * | 1983-07-06 | 1986-01-28 | Mitsubishi Denki Kabushiki Kaisha | Control apparatus for elevator |
US5119071A (en) * | 1989-07-10 | 1992-06-02 | Sanyo Electric Co., Ltd. | Method and apparatus for controlling induction motor for compressor |
US5313151A (en) * | 1991-05-14 | 1994-05-17 | Rotork Controls Limited | Induction type electric motor drive actuator system |
US5418451A (en) * | 1991-11-15 | 1995-05-23 | Heidelberger Druckmaschinen Ag | Apparatus for measuring at least one state variable of a brushless direct-current motor |
US5811957A (en) * | 1995-12-21 | 1998-09-22 | General Motors Corporation | Speed sensorless hybrid vector controlled induction motor with zero speed operation |
US6718273B1 (en) * | 1999-06-22 | 2004-04-06 | Robert Bosch Gmbh | Methods for simplified field-oriented control of asynchronous machines |
US7199549B2 (en) * | 2001-08-17 | 2007-04-03 | Delphi Technologies, Inc | Feedback parameter estimation for electric machines |
US7268514B2 (en) * | 2004-11-30 | 2007-09-11 | Rockwell Automation Technologies, Inc. | Motor control for stopping a load and detecting mechanical brake slippage |
US7475557B2 (en) * | 2003-12-22 | 2009-01-13 | Kabushiki Kaisha Toshiba | Refrigerator |
US7770406B2 (en) * | 2003-11-28 | 2010-08-10 | Kabushiki Kaisha Toshiba | Refrigerator |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3205460A1 (en) | 1982-02-16 | 1983-02-03 | Martin 7430 Metzingen Graser | Contactless, feedback-free temperature measurement using permanent magnet, calibration curve and Hall generator |
DE19539711C2 (en) * | 1995-10-25 | 2002-08-29 | Tech Gmbh Antriebstechnik Und | Tracking the rotor time constants for field orientation |
DE19650908A1 (en) * | 1995-12-22 | 1997-06-26 | Papst Motoren Gmbh & Co Kg | Electronically commutated motor design |
JPH10174276A (en) | 1996-12-06 | 1998-06-26 | Matsushita Electric Ind Co Ltd | Motor protection device |
DE19942205A1 (en) | 1999-09-03 | 2001-03-15 | Sew Eurodrive Gmbh & Co | Control method for a converter for field-oriented control of an electric motor and converter |
JP4165229B2 (en) | 2003-01-14 | 2008-10-15 | トヨタ自動車株式会社 | Permanent magnet temperature sensor, permanent magnet motor, permanent magnet motor drive system |
JP2005061709A (en) | 2003-08-11 | 2005-03-10 | Toshiba Corp | Cooling fan driving device of refrigerator |
-
2008
- 2008-01-29 DE DE502008003332T patent/DE502008003332D1/en active Active
- 2008-01-29 AT AT08001598T patent/ATE507465T1/en active
- 2008-01-29 EP EP08001598A patent/EP1992927B1/en not_active Not-in-force
- 2008-04-15 DE DE102008018843A patent/DE102008018843A1/en not_active Withdrawn
- 2008-04-30 US US12/112,130 patent/US7936145B2/en not_active Expired - Fee Related
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3848466A (en) * | 1974-01-30 | 1974-11-19 | Atomic Energy Commission | Magnetic temperature sensor |
US4567419A (en) * | 1983-07-06 | 1986-01-28 | Mitsubishi Denki Kabushiki Kaisha | Control apparatus for elevator |
US5119071A (en) * | 1989-07-10 | 1992-06-02 | Sanyo Electric Co., Ltd. | Method and apparatus for controlling induction motor for compressor |
US5313151A (en) * | 1991-05-14 | 1994-05-17 | Rotork Controls Limited | Induction type electric motor drive actuator system |
US5418451A (en) * | 1991-11-15 | 1995-05-23 | Heidelberger Druckmaschinen Ag | Apparatus for measuring at least one state variable of a brushless direct-current motor |
US5811957A (en) * | 1995-12-21 | 1998-09-22 | General Motors Corporation | Speed sensorless hybrid vector controlled induction motor with zero speed operation |
US6718273B1 (en) * | 1999-06-22 | 2004-04-06 | Robert Bosch Gmbh | Methods for simplified field-oriented control of asynchronous machines |
US7199549B2 (en) * | 2001-08-17 | 2007-04-03 | Delphi Technologies, Inc | Feedback parameter estimation for electric machines |
US7770406B2 (en) * | 2003-11-28 | 2010-08-10 | Kabushiki Kaisha Toshiba | Refrigerator |
US7475557B2 (en) * | 2003-12-22 | 2009-01-13 | Kabushiki Kaisha Toshiba | Refrigerator |
US7268514B2 (en) * | 2004-11-30 | 2007-09-11 | Rockwell Automation Technologies, Inc. | Motor control for stopping a load and detecting mechanical brake slippage |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102594032A (en) * | 2011-01-14 | 2012-07-18 | 瑞美技术有限责任公司 | Electric machine having an integrated rotor temperature sensor |
US20120181882A1 (en) * | 2011-01-14 | 2012-07-19 | Remy Technologies, L.L.C. | Electric machine having an integrated rotor temperature sensor |
US20120187888A1 (en) * | 2011-01-25 | 2012-07-26 | Marco Bussa | Voltage regulating device |
US9713270B2 (en) * | 2011-01-25 | 2017-07-18 | Gate S.R.L. | Voltage regulating device |
US20140355644A1 (en) * | 2013-05-31 | 2014-12-04 | Purdue Research Foundation | Wireless Sensor for Rotating Elements |
US9383267B2 (en) * | 2013-05-31 | 2016-07-05 | Purdue Research Foundation | Wireless sensor for rotating elements |
CN107192972A (en) * | 2017-05-17 | 2017-09-22 | 常楚笛 | A kind of MRI system and its imaging method |
Also Published As
Publication number | Publication date |
---|---|
ATE507465T1 (en) | 2011-05-15 |
US7936145B2 (en) | 2011-05-03 |
DE102008018843A1 (en) | 2008-11-20 |
EP1992927A1 (en) | 2008-11-19 |
DE502008003332D1 (en) | 2011-06-09 |
EP1992927B1 (en) | 2011-04-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7936145B2 (en) | Electronically commutated asynchronous motor | |
EP2559971B1 (en) | Rotation angle detection device | |
US9909853B2 (en) | Calibration and monitoring of an angle measuring system for electrical machines | |
US9438152B2 (en) | Electronically commutated electric motor comprising rotor position detection with interference field compensation | |
US10971981B2 (en) | Position sensor and method for generating a sensor output signal | |
JP2018029472A (en) | Position estimation method and position control device | |
US10099719B2 (en) | Apparatus and method for measuring offset of EPS motor position sensor | |
US20160043676A1 (en) | Method for operating a multiphase electric machine and corresponding multiphase electric machine | |
JP2004045286A (en) | Method of correcting resolver | |
US9742425B2 (en) | Rotation detector and rotation detection method | |
US8836262B2 (en) | Method and arrangement for determining the dynamic state of an electric motor | |
US10505482B2 (en) | Magnetic pole direction detection device | |
JP2021129440A (en) | Control device and control method of permanent magnet motor | |
US9719807B2 (en) | Method for precise position determination | |
US7045982B2 (en) | Driving circuit for brushless motor | |
US10819263B2 (en) | Method for determining the angular position of the rotor of an inverter-fed synchronous motor, and an apparatus for carrying out the method | |
US12032026B2 (en) | Measuring circuit of the voltage of an electric machine, system and process for estimating the temperature of the magnets of electric machines using such circuit | |
WO2021166550A1 (en) | Control device for motor and control method | |
US12007234B2 (en) | Magnitude calculation in a magnetic field angle tracking system | |
JP2009225545A (en) | Brushless motor controller, brushless motor, and setting method of brushless motor controller | |
JP2022089270A (en) | Control device of motor | |
JP2021027652A (en) | Control device of electric motor | |
EP4111218A1 (en) | Measuring circuit of the voltage of an electric machine, system and process for estimating the temperature of the magnets of electric machines using such circuit | |
JP2000122733A (en) | Current controller equipped with error correcting function by temperature | |
JP2023005339A (en) | Electric motor control device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: EBM-PAPST ST. GEORGEN GMBH & CO. KG, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SCHMID, HARALD;REEL/FRAME:020884/0906 Effective date: 20080429 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
REMI | Maintenance fee reminder mailed | ||
FPAY | Fee payment |
Year of fee payment: 4 |
|
SULP | Surcharge for late payment | ||
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 8 |
|
FEPP | Fee payment procedure |
Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
LAPS | Lapse for failure to pay maintenance fees |
Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20230503 |